SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Schedule 13D

Under the Securities Exchange Act of 1934

(Amendment No. )*

Garrett Motion Inc.

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

366505105

(CUSIP Number)

Attestor Limited

7 Seymour Street

London W1H 7JW, United Kingdom

Attention: Friedrich S. Andreae

Telephone: +44 (0) 20 7074 9610

with a copy to

Robert A. Profusek

Jones Day

250 Vesey Street

New York, New York 10281

(212) 326-3800

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

October 20, 2020

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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Item 1. Security and Issuer

This statement of beneficial ownership on Schedule 13D relates to the shares of common stock, $0.001 par value per share (the “Shares”), of Garrett Motion Inc., a Delaware corporation (the “Company”). According to the Company, the address of its principal executive office is La Pièce 16, Rolle, Switzerland 1180.

Item 2. Identity and Background

Item 3. Source and Amount of Funds or Other Consideration

Attestor invested $7,557,901 to purchase 2,661,970 Shares. The source of funds was Attestor’s capital available for investment. The Reporting Persons may effect purchases of Shares through margin accounts maintained for it with brokers, which extend margin credit as and when required to open or carry positions in their margin accounts, subject to applicable federal margin regulations, stock exchange rules and such firms’ credit policies. Positions in Shares may be held in margin accounts and may be pledged as collateral security for the repayment of debit balances in such accounts. Such margin accounts may from time to time have debit balances. Because other securities may be held in such margin accounts, it may not be possible to determine the amounts, if any, of margin used to purchase Shares.

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Item 4. Purpose of Transaction

On October 20, 2020, the Reporting Persons and other Company shareholders (the “Other Shareholders” and, together with the Reporting Persons, the “Shareholder Parties”), Oaktree Capital Management, L.P. (“Oaktree”), Centerbridge Partners, L.P., (“Centerbridge” and, together with Oaktree and the Shareholder Parties, the “Equity Commitment Parties”) and Honeywell International Inc. (“Honeywell”) entered into the Amended and Restated Coordination Agreement (including the term sheet attached thereto, the “A&R Coordination Agreement”) in anticipation of submitting an alternative proposal for a plan of reorganization (the “Proposed Plan”) to the Company. The A&R Coordination Agreement amended and restated a similar agreement entered into by Oaktree, Centerbridge and Honeywell announced on October 16, 2020.

Under the A&R Coordination Agreement, among other things, the Equity Commitment Parties agreed to backstop the issuance of, or otherwise commit to purchase, $1,050.0 million of new shares of Convertible Series A Preferred Stock (the “Convertible Series A Preferred Stock”) of the reorganized Company. The restructuring transactions contemplated by the A&R Coordination Agreement provide for the treatment of claims against the Company and its subsidiaries, and a rights offering in which all holders of Shares will receive subscription rights to purchase additional shares of Convertible Series A Preferred Stock at a purchase price of up to $100.0 million in the aggregate in cash pursuant to the terms and conditions therein. Under the A&R Coordination Agreement, among other things, the Shareholder Parties agreed not to dispose of any ownership, including any Beneficial Ownership (as defined in SEC Rule 13d-3) in any interests in the Debtors (as defined therein) unless the A&R Coordination Agreement is terminated with respect to the Shareholder Parties and such termination is disclosed in an amendment to their respective Schedule 13Ds. The A&R Coordination Agreement may be terminated by Shareholder Parties holding at least 60% of the commitments to purchase Convertible Series A Preferred Stock held by the Shareholder Parties following the occurrence of certain events set forth therein.

The Proposed Plan has not been approved by the Company and is subject to milestones and conditions that may not occur or be satisfied. As such, there is no assurance that the Proposed Plan will be completed on the terms set forth in the A&R Coordination Agreement, or at all. The foregoing description of the A&R Coordination Agreement is qualified in its entirety by the terms and conditions of the A&R Coordination Agreement, which is filed as Exhibit 99.1 hereto.

The Shareholder Parties by themselves or with the Equity Commitment Parties (to the extent they own Shares) may be deemed to constitute a group for purposes of Rule 13d-3 under the Act. The Reporting Persons anticipate that the other Equity Commitment Parties will file separate statements of beneficial ownership on Schedule 13D pursuant to Rule 13d-1(k)(2) under the Act containing their required information. The Reporting Persons assume no responsibility for the information contained in any filings by any other person. The Reporting Persons expressly disclaim beneficial ownership of any securities beneficially owned or acquired by any other person except to the extent of their pecuniary interest therein. Based on information provided by the other Equity Commitment Parties, the Reporting Persons believe that the Equity Commitment Parties beneficially own in the aggregate 49.3% of the outstanding Shares as of the date of this Schedule 13D.

The Reporting Persons intend to review their investment in the Company on a continuing basis and, depending upon the price of and other market conditions relating to the Shares, developments affecting the Company and the Chapter 11 case and other factors deemed relevant, subject to the terms of the A&R Coordination Agreement, the Reporting Persons may increase or decrease the size of their investment in the Company, pursue changes in the composition of the Company’s Board of Directors or propose or take one or more other actions that relate to or would result in any matter referred in items (a) through (j) of Item 4 of Schedule 13D, alone or with others. The Reporting Persons reserve the right, subject to the terms of the A&R Coordination Agreement, to act independently and without respect to the other Equity Commitment Parties, to change their plans or proposals at any time, and to take any action as they deem appropriate, either alone or with others, in their sole discretion at any time, including with respect to any matter set forth in items (a) through (j) of Item 4 of Schedule 13D.

Item 5. Interest in Securities of the Issuer

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Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer

Except as described in this statement, there are no contracts, arrangements, understandings or relationships (legal or otherwise) among any of the Reporting Persons and between such persons any other person with respect to any securities of the Company, including, but not limited to, transfer or voting of any of such securities, finder’s fees, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, division of profits or loss or the giving or withholding of proxies.

Item 7. Materials to be Filed as Exhibits

The following documents are filed as exhibits to this statement:

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SIGNATURE

After reasonable inquiry and to the best of his knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: October 26, 2020

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SCHEDULE A

Transactions in Shares effected by Attestor Value Master Fund LP in the last 60 days

(all purchases and sales effected on the New York Stock Exchange)

EXHIBIT 99.2

JOINT FILING AGREEMENT

In accordance with Rule 13d–1(k)(1) under the Securities Exchange Act of 1934, as amended, each of the undersigned hereby agrees to the joint filing, along with such other undersigned, on behalf of the Reporting Persons (as defined in the joint filing), of a statement on Schedule 13D (including any amendments thereto) with respect to the shares of common stock, $0.001 par value per share, of Garrett Motion Inc. beneficially owned by each of them, and agrees that this Joint Filing Agreement be included as an exhibit to such joint filing. This Joint Filing Agreement may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the undersigned executed this Joint Filing Agreement as of October 26, 2020.